1. Introduction to 8th Grade General Science

2. THE SCIENTIFIC METHOD

3. THREE BRANCHES OF SCIENCE
Can you name them?
PHYSICAL SCIENCE: The study of energy. (Example: molecules in motion)
EARTH SCIENCE: The study of the inorganic components of the Earth. (Example: Weather and rocks)
LIFE SCIENCE: The study of living things. (Example: Animals and plants)

4. BRANCHES OF EARTH SCIENCE
Can you name them?
GEOLOGY: The study of the history of the Earth. (Example: Rocks and plate tectonics)
METEOROLOGY: The study of the Earth’s atmosphere. (Example: Weather and climate)
ASTRONOMY: The study of the Universe. (Example: Stars and space)

5. How do scientists obtain new information?
Observation
Experimentation
Discovery

6. What is an observation?
An observation is a description of an object or event by using one of the 5 senses.
It is 100% true statement; a fact.

7. Observation:
The grass is wet.

8. What is an inference?
An inference is to explain observations based on complete information.
You are inferring something based on factual information.
100% opinion!

9. Inference:
It rained outside.

10. What is the Scientific Method?
The scientific methods are the ways in which scientists answer questions and solve problems.
There are 8 steps to the scientific method.

11. THE STEPS OF THE SCIENTIFIC METHOD
Purpose: Question
Research
Hypothesis
Experiment
Observation (Analyze Data)
Conclusion
Ask a new question
Repeat Experiment

12. Parts of an Experiment
Controlled experiment – an experiment where the scientist controls all the variables except the ONE variable being tested.
1. Experimental Group: part of the experiment that is being tested.
2. Control Group: the part of the experiment that stays the same.
3. Independent Variable – The 1 thing that differs between both groups.
4. Control Factors – all the things that are kept the same between both groups.
5. Dependent Variable – the variable that is not controlled by the scientist. It will be the result of his experiment.

13. What is a hypothesis? IF, THEN, BECAUSE!
A hypothesis is a suggested answer to a problem WITHOUT the support of data. An educated guess.
A hypothesis is made BEFORE the experiment is performed.
A hypothesis is always written as:
IF, THEN, BECAUSE!

14. Put it together: Observation: The grass is wet.
Interpretation/inference: The grass is wet because it rained outside.
Hypothesis: If it rained outside, then the grass will still be wet because the sun didn’t dry off the water.

15. Group 1 Group 2 What’s DIFFERENT?
3 trees
All have same volume of water and same amount of sunlight
3 trees
All have same volume of water, same amount of sunlight, and same amount of fertilizer
What’s DIFFERENT?
The fertilizer. The fertilizer is the INDEPENDENT VARIABLE.

16. Group 1 Group 2 Which is the CONTROL GROUP?
3 trees
All have same volume of water and same amount of sunlight
3 trees
All have same volume of water, same amount of sunlight, and same amount of fertilizer
Which is the CONTROL GROUP?
GROUP 1 is the control group because to find out if the fertilizer worked, you need to compare it with something that doesn’t have fertilizer.

17. Experimental Group Control Group
3 trees
All have same volume of water and same amount of sunlight
All have same volume of water, same amount of sunlight, and same amount of fertilizer
Fertilizer is the (different).
This is the control group because it doesn’t have the fertilizer.
This is the experimental group because it is why you are doing the experiment.

18. Two types of variables
Independent variable: is the variable you change in the experiment
Dependent variable: is the variable you are measuring
Example: You want to measure the effect of the sun on plant growth.
What you change?
What you measure?
Amount of sunlight
Growth

19. The effect of the SUN on the GROWTH of plants.
INDEPENDENT VARIABLE
on the
DEPENDENT VARIABLE.
The effect of the SUN on the GROWTH of plants.

20. More examples The effect of sunlight on the growth of plants.
The effect of cold medicine on the number of sneezes.
The effect of bleach on the growth of bacteria.
Independent Variable (IV)
Dependent Variable (DV)

21. What makes a good experiment?
Repeating the experiment. Every scientist from around the world should be able to repeat your experiment and obtain the exact same results.